I have read the original post on this topic, when "E525 black screen" is searched for or something similar. I refer to this post below.

Before I alter the line in GRUB mode the line reads: "...quiet splash $vt_handoff"

I have entered the GRUB mode and added "nomodeset" after "quiet splash", I press ctrl+X to boot and Ubuntu loads however, the resolution is poor and the dimensions of the display are generally displeasing.

When I restart from this situation I get a black screen with vertical line pattern.

The frustrating thing is I can turn the computer off by holding down the power button and turn it back on and it willload just fine pretty much every other time.

My problem is simply that when I power up my laptop around 50% of the time, the Thinkpad logo will appear as the system powers up, then it goes away, but the Ubuntu login screen never appears, the screen just stays black. The other 50% of the time, the Thinkpad logo will appear as the system powers up, and the Ubuntu login screen does appear and it works just fine.

I recently followed some instructions from another post you replied to, I altered the GRUB boot line in the manner I mentioned earlier, but the problem hasn't changed since I did this. As you say the changes only remain for one boot. Though a few times after I did this my laptop would go straight into the GRUB menu on power up, again randomly, but this has not happened for a number of power ups now. When this did happen I would just choose the top option and it would work fine.

Thank you for your help, I hope I am giving you some something to go on.